The objective of this model is to develop a mouse skin paint model which will allow for the rapid screening and ranking of chemopreventive agents. Groups of mice will e treated three times per week with 3 different doses of benzo(a)pyrene on the skin. Concurrently treated will administered chemopreventive agents in drinking water. The specific agents to be examined are all extracts or specific components of green or black teas. A number of these agents have been previously shown to be effective in other mouse skin tumor models. The contractor shall determine the development of tumors on the backs of treated mice and thereby generate data showing examining the relationship between the effects of an agent on tumor latency and multiplicity at a variety of doses of carcinogen. This may prove to be a relatively easy method to determine efficacy of agents effective in treating epithelial cell cancers.